The world champions need just a point in Dublin next Saturday to qualify for June's finals in South Africa as Group Eight winners.
Coach Marcello Lippi has therefore resisted major changes following their best performance in months in September's 2-0 victory over Bulgaria.
World Cup winner Gattuso missed the win with an ankle injury but has been recalled for the Irish trip and October 14's final group game with Cyprus in Parma despite his club's poor recent form.
Cassano, one of the best players in Serie A for the past two seasons having previously been undermined by childish antics, had been backed by fans and pundits for a recall.
Genoa defender Salvatore Bocchetti returned to the squad at the expense of team mate Domenico Criscito while Fiorentina centre back Alessandro Gamberini was also called up for the first time since the Confederations Cup in June.
Captain Fabio Cannavaro was included despite not being fully fit and being suspended for the game against Giovanni Trapattoni's second-placed Ireland.
Fiorentina winger Marco Marchionni missed out along with strikers Luca Toni and Giampaolo Pazzini.
Goalkeepers: Gianluigi Buffon (Juventus), Morgan De Sanctis (Napoli), Federico Marchetti (Cagliari)
Defenders: Fabio Cannavaro (Juventus), Giorgio Chiellini (Juventus), Salvatore Bocchetti (Genoa), Alessandro Gamberini (Fiorentina), Fabio Grosso (Juventus), Nicola Legrottaglie (Juventus), Davide Santon (Inter Milan), Gianluca Zambrotta (AC Milan)
Midfielders: Mauro Camoranesi (Juventus), Gaetano D'Agostino (Udinese), Daniele De Rossi (AS Roma), Gennaro Gattuso (Milan), Claudio Marchisio (Juventus), Angelo Palombo (Sampdoria), Simone Pepe (Udinese), Andrea Pirlo (Milan)
Forwards: Antonio Di Natale (Udinese), Alberto Gilardino (Fiorentina), Vincenzo Iaquinta (Juventus), Fabio Quagliarella (Napoli), Giuseppe Rossi (Villarreal)
